Cart-leg connection

ABSTRACT

A shelf-leg connection in which said shelf is provided with a peripheral skirt connected to a tubular leg. A mating rib and recess are formed in said skirt and leg, respectively. A bracket corresponding in shape to said rib is carried against the inner face of said rib and said rib is bindingly retained between said leg recess and bracket by a bolt extending therethrough.

United States Patent 11 1 Basey 1 CART-LEG CONNECTION [75] Inventor: Otis Basey. Columbus. Ind

[73] Assignee: Cosco. Inc., Columbus. Ind.

[22] Filed: Dec. 28, 1973 211 Appl. No.: 429.379

[52] US. Cl. 108/156; 108/111; 248/188 [51] Int. Cl t. A4711 7/00 {58] Field of Search 108/111, 153.156, 158; 248/188, 188.1; 211/148. 177. 133, 126, 153, 135

[56] References Cited UNITED STATES PATENTS 3.181693 6/1965 Hamilton et al 1. 248/188 32049OS 9/1965 Marban v e v e 248/188 3.599.580 8/1971 Adair et a1 211/148 1 June 10, 1975 FOREIGN PATENTS OR APPLICATIONS 70.682 6/1959 France 248/188 1,265,960 5/1961 France 248/188 Primary ExaminerRoy D. Frazier Assistant E.raminerDarrell Marquette Attorney, Agent, or Firm-Trask, Jenkins & Hanley [57] ABSTRACT A shelf-leg connection in which said shelf is provided with a peripheral skirt connected to a tubular leg. A mating rib and recess are formed in said skirt and leg. respectively. A bracket corresponding in shape to said rib is carried against the inner face of said rib and said rib is bindingly retained between said leg recess and bracket by a bolt extending therethrough.

4 Claims, 5 Drawing Figures CART-LEG (.ONNECTION BACKGROUND OF THE INVENTION This invention generally relates to metal furniture. and more specifically. to an improved structure for connecting a metal shelf to a leg.

Metal furniture such as serving carts, tray tables. and the like are old in the art and are often constructed of lightweight materials such as metal-stamped shelves and legs of steel tubing. Such shelves commonly inelude a downwardly projecting peripheral skirt to which the legs are connected as by bolts extending through holes formed in said skirt and legs.

The connection between the leg and the shelf skirt has an annoying tendency to work loose. since many metal furniture items such as serving carts are regularly moved from place to place and subjected to a certain amount of jostling about. The bolt alone simply does not keep the leg and the shelf tightly and permanently fastened together, and a periodic re-tightening of the connection is required.

Various schemes have been employed to remedy this continual working loose of the connection. In one such scheme a standard circular-shaped lock washer is used in a conventional fashion with the connecting bolt to retain the leg and the shelf connection in a permanently tightened condition. Lock washers. because of the irregular surface nature of the shelf skirt and the leg tubing, have not been satisfactory because they do not engage sufficient surface area to lend the required sup' port and stability to the connection to overcome the tendency of the connection to work loose during normal use.

The present invention overcomes the problems and difficulties encountered throughout the prior art by providing a metal furniture shelf-leg connection which maintains the leg and shelf in a permanently fastened condition. and which is also easy to use and inexpensive to manufacture.

SUMMARY OF THE INVENTION In accordance with one form of the invention, as it is embodied in a serving cart, there is provided one or more shelves each having a peripheral border skirt formed in a plane normal to the general plane of the shelf and to which is connected a plurality of legsv At each shelf-leg connection. a rib is formed in the shelf skirt and projects outwardly therefrom. A generally correspondingly'shaped bracket abuts the inner face of said rib, and a generally correspondingly-shaped recess formed in the leg abuts the outer face of said rib. Said leg, skirt, and bracket have aligned holes formed therein for the reception of a retaining bolt extending therethrough and drawing the leg. skirt. and bracket into binding engagement to form a solid and permanently tightened shelf-leg connection.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings illustrate the invention. In such drawings:

FIG. I is a perspective view of a cart having shelf-leg connections embodying this invention:

FIG. 2 is an enlarged vertical section taken along the line 22 of FIG. I;

FIG. 3 is an exploded assembly view of a leg connection to the upper shelf;

FIG. 4 is an enlarged horizontal section taken along the line 44 of FIG. I; and

FIG. 5 is an exploded assembly view of a leg connection to the lower shelf shown in FIG. 4.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A cart I0 having shelf-leg connections embodying the invention is shown in FIG. I and generally com prises an upper shelf I2 and a lower shelf I4, each of which is coupled as will be hereinafter described to a plurality of laterally spaced legs 16. Conveniently, casters I8 can be mounted on the lower ends of the legs 16 to facilitate movement of the cart from one location to another.

The upper and lower shelves I2 and 14 are each formed of a lightweight sheet-metal stamping, or the like. Each such shelf has a downwardly dished horizontal supporting surface 20 and a downwardly projecting peripheral border skirt 22 disposed normal to the plane of the supporting surface 20. As shown, the shelves I2 and I4 can be generally rectangular in shape and are thus coupled near all four corners thereof by their respective peripheral skirts 22 to the legs 16.

The legs 16 are formed as a pair of generally inverted U-shaped frames 24 fabricated from lightweight steel tubing or the like. Each frame 24 includes a pair of laterally spaced legs I6 interconnected at their upper ends by a transverse bight 26. Conveniently, the bight 26 is slightly longer than the width of the shelves l2 and 14 so that the legs 16 can be coupled to the outer faces of the shelf skirts 22. This permits the upper portion of each frame 24 to be turned horizontally at the upper shelf connection as shown in FIG. I and to extend longitudinally outwardly in the plane of the upper shelf 12 so that the bight 26 of each frame 24 can also serve as a handle for the cart 10. Moreover, with this construe tion, the horizontal portion of each frame 24 has a stretch disposed adjacent to and alongside the upper shelf skirt 22 to permit each of the legs I6 to be coupled to the upper skirt by a plurality of connecting bolts as will be hereinafter explained.

Each leg-upper shelf connection is identical, and as shown in FIGS. 2 and 3, at each such connection, an elongated rib 28 is formed in and extends outwardly from the shelf skirt 22. As shown in FIG. 3, the rib has a generally V-shaped cross-section with the apex 29 of said cross-section extending along the longitudinal axis of said rib. A recess 30 corresponding in shape to, but slightly longer than. the rib 28 is formed in the adjacent inner face of the leg 16 adjacent the rib 28. As shown in FIG. 3, pairs of longitudinally spaced holes 3] and 33 are formed in the rib 28 and recess 30, respectively. The holes 31 and 33 are formed in alignment with each other along the apexes of said rib and recess.

An elongated bracket 32 having a length slightly shorter than the length of the rib 28 and a V-shaped cross-section is disposed along the inner face of the shelf skirt 22 within the extent of rib 28. Bracket 32 has a configuration generally corresponding to that of the rib and recess so that the rib 28 is matingly received between the recess 30 and the bracket 32. A pair of holes 44 are formed in said bracket along the apex 45 of its V-shaped cross-section. the holes 44 are longitudinally spaced apart a distance equal to the longitudinal spacing of the rib and recess holes 3] and 33, respectively. A bolt 34 extends through each set of the aligned holes 33, 31 and 44 and is threadably received in a nut 35 carried against the inner face of the bracket 32. Thus. as the bolt 34 is drawn up on the nut. the apex 45 of the bracket 32 is drawn into abutting engagement with the inner face of the apex 29 of the rib 28 to matingly locate said rib within the recess 30 and thereby bindingly connect the leg 16 to the shelf skirt 22. As shown in H6. 2, the nut has a cross-sectional extent slightly smaller than the cross-sectional extent of the bracket 32 so that said bracket will prevent the nut from turning on the bolt after the bolt has been tightened thereon. Conveniently. the leg is recessed around each of the holes 33. as at 36. to permit the heads of the bolts 34 to be countersunk in the outwardly presented leg faces.

in forming the \"-shape crossscctions in the recess 30 and bracket 32, they should each define an included angle of from about 90 to about 150, and preferably l20". Each rib 28 should define an included angle of from about 140 to about 160. and preferrably l5(). The angle formed by the rib 28 should be slightly greater than the included angle formed by the bracket 32 and/or the recess 30 to assure that the apex of the bracket abuts the apex 29 of the rib 28 along the inner face of the skirt 22 to cause the rib to be drawn into the recess 30 under spring tension when the components are tightened together. This assures that the components will remain together in close and binding engage ment. and will not work loose over a period of time.

If desired, the inwardly presented face in each of the legs 16 adjacent the recess 30 is flattened. as at 43. This permits the legs 16 to closely abut the underlying outer face of the upper shelf skirt 22 in the vicinity of the shelf-leg connection to further promote a solid. stable.

and permanent interonnnection between the shelf and each leg.

The connections of the legs 16 to the lower shelf 14 are similar to their connections to the upper shelf. While only one lower shelf-leg connection is shown in FIGS. 4 and S by way of example. the remaining three lower shelf-leg connections are identical thereto. An outwardly projecting rib is formed on the outer face of the peripheral skirt 22 of the lower shelf 14 adjacent each point of connection to a leg 16. Each rib S0 is generally V-shaped in cross-section and is similar to the ribs 28 formed on the upper shelf 12 with the exception that the apex 51 of its V-shaped corss-section extends vertically and is thus limited in length by the approximate height of the lower shelf skirt 22. A connecting hole 52 is formed through the rib 50 at its apex 51 through which a lower shelf retaining bolt 54 extends for connection to a nut 56.

A vertically extending recess is formed in the inwardly presented face of leg 16 at the point of connection to the lower shelf skirt 22. The recess 60 has a V- V shaped cross-section corresponding to the crosssection of the lower shelf rib 50. The recess 60 has a length slightly longer than the length of the rib 50 to permit the rib to be received in the recess. and has a connecting hole 62 formed therein at its apex in alignment with the rib hole 52 for reception of the bolt 54. As shown. the hole 62 is counter-sunk in the outwardly presented leg face to permit the head of bolt 54 to lie relatively flush with the outer surface of the leg 16.

Moreover. like the upper shelf connection. the inwardly presented leg face is flattened. as at 61. in the vicinity of the lower shelf connection to abut the adjacent surface of the shelf skirt to insure a tight and Close fit between the leg 16 and the lower shelf 14.

A bracket 64 is provided for each lower shelf-leg connection and is similar to the upper shelf bracket 32 with the exception that it is shorter in length. being slightly less than the length of the rib S0. The bracket 64 has a V-shaped cross-section with a hole 66 formed therein at the apex of said V-shaped cross-section for reception of the bolt 54. The bracket 64 is posi tioned along the inner face of the skirt 22 of the lower shelf with its apex 65 in abutting engagement with the inner face of the apex 51 of the rib 50.

The V-shaped cross-sections of the rib S0. recess 60. and bracket 64 have the same angular relationships as the rib 28. recess 30. and bracket 32 in the upper shelf connection. Thus. with the bolt 54 extending through the aligned openings in the recess 60. rib 50. and bracket 64. and the nut 56 drawn up on said bolt. a binding connection will be formed between the shelf and leg. And with the nut engaging the angulated inwardly presented rib faces. said nut will be prevented from turning on said bolt.

I claim:

1. A shelf-leg connection for an article of metal furniture including a sheet-metal shelf having a peripheral border skirt lying in a plane normal to the general plane of said shelf and coupled to at least one leg formed of metal tubing. said connection comprising an outwardly projecting V-shaped rib formed in said skirt. said leg having a V-shaped recess formed therein generally corresponding in shape to the shape of said rib. a sheetmetal bracket having a V-shaped cross-section disposed along the inner face of said rib. said rib being matingly engageable between said bracket and recess. a bolt extending through aligned openings formed in said recess. rib. and bracket. and a nut drawn up on said bolt for bindingly interconnecting said bracket and recess with said rib disposed therebetween. said nut having a cross-sectional extent less than said bracket whereby said bracket will prevent said nut from turning after it has been drawn up on said nut.

2. A shelf-leg connection as set forth in claim 1 wherein said recess. rib, and bracket are elongated with the apexes of their V-shaped cross-sections extending along their longitudinal axes. said recess having a length longer than the length of said rib. and said bracket having a length shorter than the length of said rib.

3. A shelf leg connection as set forth in claim 1 wherein said recess. rib. and bracket are elongated. and the cross-section of said rib defines an included angle of from about [40 to about l6(). and the cross-section of said recess and said bracket each define an included angle of from about to about l5().

4. A shelf-leg connection as set forth in claim I wherein said recess. rib. and bracket are elongated. and the included angle defined by the cross-section of said rib is greater than the included angle defined by the cross-section of said bracket. 

1. A shelf-leg connection for an article of metal furniture including a sheet-metal shelf having a peripheral border skirt lying in a plane normal to the general plane of said shelf and coupled to at least one leg formed of metal tubing, said connection comprising an outwardly projecting V-shaped rib formed in said skirt, said leg having a V-shaped recess formed therein generally corresponding in shape to the shape of said rib, a sheet-metal bracket having a V-shaped cross-section disposed along the inner face of said rib, said rib being matingly engageable between said bracket and recess, a bolt extending through aligned openings formed in said recess, rib, and bracket, and a nut drawn up on said bolt for bindingly interconnecting said bracket and recess with said rib disposed therebetween, said nut having a cross-sectional extent less than said bracket whereby said bracket will prevent said nut from turning after it has been drawn up on said nut.
 2. A shelf-leg connection as set forth in claim 1 wherein said recess, rib, and bracket are elongated with the apexes of their V-shaped cross-sections extending along their longitudinal axes, said recess having a length longer than the length of said rib, and said bracket having a length shorter than the length of said rib.
 3. A shelf-leg connection as set forth in claim 1 wherein said recess, rib, and bracket are elongated, and the cross-section of said rib defines an included angle of from about 140* to about 160*, and the cross-section of said recess and said bracket each define an included angle of from about 120* to about 150*.
 4. A shelf-leg connection as set forth in claim 1 wherein said recess, rib, and bracket are elongated, and the included angle defined by the cross-section of said rib is greater than the included angle defined by the cross-section of said bracket. 